What is manifest file?

[Suvojit Chakraborty]

Hi,
I have learned about jar's. I know the basic definition of the manifest file.I know that it gets created automatically and that it stores information like version number etc.
But I want to know following :
1.Is it possible to create manifest file manually, overwriting the default one created automatically?
2.What other information does the manifest file stores?
3.Will it be right to say that it is a metadata of the jar file.
4.What is the exact use of the Manifest file?

Thank you to clear my doubts.

BR
Suvojit

[Ulf Dittmer]

Start here: http://java.sun.com/docs/books/tutorial/deployment/jar/index.html (and bookmark the Java Tutorial, it will come in handy many times)

[Rob Spoor]

Please read http://java.sun.com/docs/books/tutorial/deployment/jar/build.html for question 1 and http://java.sun.com/docs/books/tutorial/deployment/jar/manifestindex.html for the rest of your questions.